基于Python的串口通信(2).doc

基于Python的串口通信(2)Pyvisa1.1 安装pyvisa1.1.1 source安装(1) 下载pyvisa 说明文档：/en/latest/ 下载链接：/hgrecco/pyvisa /(2) 解压 命令解压cd /xxx/xxx/pyvisa-master.zip（切换到相关文件所在目录）tar zxvf pyvisa-master.zip 手动解压（Mac下像.zip类的格式一般会在Safari下载完成后自动解压）(3) 安装visa module cd /xxx/xxx/pyvisa-master（切换到解压后的文件所在目录） sudo python setup.py install（加sudo以避免权限问题：”Permission denied.”） 注：pyvisa 是依托于enum34的，如果是首次安装，还需要先下载enum34并安装： /pypi/enum34/1.0.4 安装方法同上：1.1.2 pip安装 sudo pip install pyvisa注：上图中之所以写成pip3.5（pip/pip3）是因为系统里除了自带的Python2外，还装了Python3（pip3为默认pip）。1.2 安装NI-VISApyvisa是基于NI-VISA库的，所以要正常的使用，还需要安装NI的VISA库：/visa/下载链接：/download/ni-visa-14.0.1/5023/en/1.3 visa通信测试1.3.1 USB模式在IDLE中进行如下测试： import visa rm = visa.ResourceManager() rm.list_resources()(uUSB0:0x0957:0x1A07:MY53203784:INSTR,) my_instrument = rm.open_resource(USB0:0x0957:0x1A07:MY53203784:INSTR) print(my_instrument.query(*IDN?)Agilent Technologies,34461A,MY53203784,A.01.09-02.25-01.09-00.35-01-01 附：一个简单的测试脚本（.py文件）visa#!/usr/bin/env python# -*- coding: utf-8 -*-import visafrom pyvisa.resources.usb import USBInstrumentfrom pyvisa.constants import *rm = visa.ResourceManager()res = rm.list_resources()#print rm#print res#print(len(res)if len(res) 0: # print(res0) for dev in res: dev_name = str(dev) if dev_name.startswith(USB): print(usb resource) usb_res = USBInstrument(rm, dev_name) usb_res.open() #usb_res = rm.open_resource(res0) idn = usb_res.query(*IDN?) print(idn) print(over) #关闭串口 usb_res.close() else: print(other resources)else: print(no dev found)1.3.2 LAN模式在IDLE中进行如下测试： import visa rm = visa.ResourceManager() rm.list_resources()(uTCPIP0:A-34461A-03784.local:inst0:INSTR,) my_instrument = rm.open_resource(TCPIP0:A-34461A-03784.local:inst0:INSTR) print(my_instrument.query(*IDN?)Agilent Technologies,34461A,MY53203784,A.01.09-02.25-01.09-00.35-01-01附：一个简单的测试脚本（.py文件） visa#!/usr/bin/env python # -*- coding: utf-8 -*-import sys, os, visa, threading, timePM = visa.instrument(TCPIP0:0:inst0:INSTR)def check_read(): #currentdir = os.curdir #fullname = os.path.join(currentdir, read_pm.txt) #fullname = os.path.join(., read_pm.txt) if os.path.isfile(read_pm.txt): read_pm() os.remove(read_pm.txt) returndef read_pm(): PM.write(FETCh:CW:POWer?) # Write file fpm_read = open(pm_read_ok.txt,w) fpm_read.write(PM.read() fpm_read.close() returndef main(): # D